yii\rbac\PhpManager::removeItem PHP Method

    public function removeItem($item)
    {
        if (isset($this->items[$item->name])) {
            foreach ($this->children as &$children) {
                unset($children[$item->name]);
            }
            foreach ($this->assignments as &$assignments) {
                unset($assignments[$item->name]);
            }
            unset($this->items[$item->name]);
            $this->saveItems();
            $this->saveAssignments();
            return true;
        } else {
            return false;
        }
    }

 /**
  * @inheritdoc
  */
 public function removeItem($item)
 {
     if (parent::removeItem($item)) {
         $this->trigger(self::EVENT_REMOVE_ROLE, new RemoveRoleEvent(['roleName' => $item->name]));
         return true;
     }
     return false;
 }